1. Field of the Invention
The present general inventive concept relates to an imaging apparatus and a method of controlling the same, and more particularly to an imaging apparatus and a method of controlling the same, which can perform divided exposure.
2. Description of the Related Art
An imaging apparatus receives light through a lens to capture an image. A light receiver of an image sensor acquires the received light, converts the acquired light into an electrical signal, and transmits the electrical signal to an image signal processor.
The light receiver may be implemented by a semiconductor device, such as a photodiode. Accordingly, if the light receiver receives light for a long time, the semiconductor device is deteriorated due to the characteristic of the semiconductor device. In general, dark current due to the deterioration increases by a factor of two whenever temperature is increased by about 6 degrees. As the dark current is increased, the characteristic of a dynamic range of an image sensor is degraded, and this exerts an influence on the picture quality.
In order to solve this problem, various methods have been proposed. For example, in order to prevent the deterioration due to the dark current, conventional methods divided the entire exposure time into n exposure times and calculated the divided exposure times using measured dark current and temperature values. According to this method, however, it is required to calculate respective independent variables for the divided exposure. Accordingly, the above-described method has drawbacks in that it is greatly influenced by the deviation of the independent variables, and therefore it is difficult to control the divided exposure times accurately. For example, since the dark current is measured after the exposure time, it becomes difficult to cope with the temperature displacement during a delay time corresponding to the exposure time. Further, since the measurement deviation of a temperature sensor for the temperature measurement exists, it is difficult to calculate accurate divided exposure times.
Accordingly, there has been a need for a technology which can measure the dark current in real time and can perform accurate divided exposure in real time.